NEW YORK CITY -- Students in New York University's telecommunications program have engineered a card reader that would let riders of the city's buses and subway trains donate value remaining on their Metrocards to charity.

The kiosk reportedly uses a magnetic stripe reader and controller that deducts the unused amount from the card and relays it to a special charitable fund. The students, who built the machine using an old tape cassette deck, are hoping to capture some percentage of the estimated $52 million that goes unclaimed during the year.